Truing device for triple cylinders of air-brakes.



' No.7|4,as|. Patented Nov. 25,1902.

- E. m. BARNES.

TRUING; DEVICE FOR TRIPLE CYLINDERS OF AIR BRAKES v (Application filedJuly 23, 1902.

(No Model.)

Fit j. 23 V 4 5 2 WJTNE'ES: INVENTOR.

fiwwmww A TTORNE 1 I cutters thereof.

UNITED STATES ATENT FFICE EDWIN M. BARNES, OF SACRAMENTO, CALIFORNIA,ASSIGNOR OF ONE- I-IALF TO ROBERT GRAHAM AND EDGAR R. M. PIERCE, OFSACRA- MENTO, CALIFORNIA.

TRUING DEVICE FOR TRIPLE CYLINDERS OF AIR-BRAKES.

SPECIFICATION forming part of Letters Patent No. 714,631, dated November25, 1902.

To a whom it may concern.-

Be it known that I, EDWIN M. BARNES, a citizen of the United States,residing at Sacramento, in the county of Sacramento and State ofCalifornia, have invented certain new and useful Improvements in TruingDevices for Triple Cylinders of Air-Brakes, of

which the following is a specification.

My invention relates to a device for truing triple cylinders ofair-brakes, the object of my invention being to provide a device of avery short time and with absolute correctness.

An important advantage of my truing device arises from the fact that theoperation thereof isnot attended by any jar, which is unavoidable inusing an emery-Wheel for grinding the bushing, as is commonly thepractice, since these emery-wheels must be runat a high speed, and hencea jar cannot be avoided. Such jar causes imperfections in the truing ofthe bushing. The advantage of my improvement is that the bushing sotrued is really more accurate than when originally turned out from thefactory if ground by an emery-wheel.

In the accompanying drawings, Figure 1 is a longitudinal section of atriple-valve casing and the improved truing device in position therein.Fig. 2 is a perspective view of the casing, thetrning device beingremoved. Fig. 3 is a side view of the cutter-stem and the bearing forsaid stem. Fig. 5 is a side view of the end collar for said bearing.Fig. 6 is an end view of the stem. Fig. 7 is a perspec-, tive View ofone of the cutters detached. Fig. 8 is a perspective view of theequalizing and adjusting nut for the cutters. Fig. 9 is a perspectiveview of the handle of the device.

Fig. 4 is a side view of the Application filed July 23, 1902- Serial No.116.750. (No model.)

Fig. 10 is a perspective view of the lock-nut, and Fig. 11 is aperspective view of the spacing-collar.

Referring to the drawings, 1 represents the casing of the triple valveof an air-brake, having the cylinder 2, provided with a bushing 3. Inthis bushing works the piston, (not here shown,) and it is this bushingwhich it is the object of my invention to accurately true. For thispurpose I insert in the seat 4 of the slide-valve a tubular bearing 5,having at one end a beveled collar or flange 6, which fits snugly in thebeveled end 7 of the slidevalve seat. The other end of said bearingreceives a collar 8, which is also provided with a flange 9, which abutsagainst the outer end of the slide-valve seat. These beveled ends servethe purpose of accurately centering the bearing in the slide-valve seat.Upon the outer end of said bearing is then passed a collar 10, of whicha number will be provided of various lengths, for the purpose ofadjusting the deviceto the length of the slide-valve seat, these seatsvarying in length. Upon the outer threaded end 11 of said bearing isthen screwed a lock-nut 12, which is screwed up very tight to firmlybind the bearing 5 within the slide-valve seat and hold the samestationary therein. Within the bearing 5 is now passed the stem or shaft13 of the cutting device. The outer end thereof has formed thereon athread 14 of very slow pitch, which thread engages an internal thread15, formed in the end of the lock-nut. Said cutter is turned by hand bymeans of a suitable double crank or handle 16, secured upon the squaredend 17 of the cutter-stem, and the rotation of said stem by theengagement of its threaded end with the thread 15 of the lock-nut causesthe cutter tobe slowly fed into the bushing. Said stem 13 has formedintegral thereon a cutter-holder 18 of a general cylindrical shape andof somewhat smaller diameter than the bushing to be trued, saidcntter-holder having formed in its periphery a suitable number, as six,of recesses 19. In each recess is held a cutter 20, said cutter beingsecured therein by means of a screw 21, passed through a slot 22 in thecutter and screwed into a screw-hole in the cutter-holder. The cutter-body is wedge-shaped in general form and is placed in the recess in thecutter-holder, so that its smaller or tapering end is directed towardthebushing. The bottom of the recess in the cutter-holder also slopesupwardly or radially outward toward the bushing, and the result is thatwhen the cutter is moved toward the bushing the effect will be to at thesame time move it radially outward.

Each cutter has formed on onecorner thereof a bit 23, which engages thebushing in the revolution of the cutter-holder, and these bits performthe function of cutting out the bushing to the required diameter andtruing the same as the cutters are revolved.

For the purpose of very accurately adj usting all the cutters toprecisely the same distance from the central axis of the cutting devicethere is also provided on the stem 13 and integral therewith a threadedenlargement 24, upon which is screwed an equalizing and adjusting nut25, having a broad inner face arranged to engage simultaneously the rearends of all the cutters. The thread of this nut 25 is of a very slowpitch. All the screws which secure the cutter in place having beenloosened and the nut 25 being screwed inward, the engagement of thefront face of said adjusting-nut with the rear ends of the cutters willadvance all of said cutters inward to precisely the same extent, therebyalso by reason of the wedge shape of the cutters and the slope of therecess moving the same radially outward to a proportional though muchsmaller extent. When all of the cutters have been accurately adjusted tothe required diameter at which it is desired to cut the bushing, theset-screws 21 are tightened and the cutting device is rotated on itsstem by hand, cutting the bushing and truing the same.

In order to more accurately adjust the cutters for the precise diameterto which it is desired to cut the bushing, there is formed upon theperiphery of the cutter-holder-between the recesses 19 a circular line26, and each of the cutters has also formed thereon a transverse line27. When the transverse lines 27 aline with the circular line 26, thebits 28 are at such distance from the center as to cut to whatis knownas the standard size of bushing. When it is desired to cut the bushingto a less diameter than the standard size, the cutters are moved inwardand when to a greaterdiameter than the standard size they are movedoutward, the extent of such movethe other was not undergoing any strainor doing any work. By providing a sufficient number of these cutters itis obtained that the strain will be distributed evenly around the Wholedevice to prevent vibration.

I claim- 1. In a device for truing cylinders of triple valves ofair-brakes, the combination of a removable bearing arranged to fitwithin the slide-valve seat, means for fixedly clamping and centeringsaid bearing in said seat, a device attached to said bearing having aninternal thread, a cutter-stem having a threaded end working in saidinternal thread, a cutterholder carried by said stem, and cutterscarried by said holder, substantially as described.

2. In a device for truing cylinders of triple valves of air-brakes, thecombination of a removable bearing arranged to fit within theslide-valve seat, means for fixedly clamping and centering said bearingin said seat, a device attached to said bearing having an internalthread, a cutter-stem having a threaded end working in said internalthread, a cutterholder carried by said stem, cutters carried by saidholder and an equalizing and adjusting nut for equally adjusting all ofsaid outters, substantially as described.

3. In a device for truing cylinders of triple valves of air-brakes, thecombination of a removable hearing arranged to fit within theslide-valve seat, means 'for fixedly clamping and centering said bearingin said seat, a device attached to said bearing having an internalthread, a cutter-stem having a threaded end working in said internalthread, a cutterholder carried by said stem, said cutter-holder havingrecesses sloping outwardly toward the bushing and wedge-shaped cutterscarried by said holder, and means for adjusting said cutterslongitudinally, substantially as described.

In witness whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

EDWIN M. BARNES.

Witnesses:

RoB. GRAHAM, EDGAR R. M. PIERCE.

